Buzzer



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IpVenbor. I Ches'tr-zr Hail 4 His Attorngy 55 tion with a pair PatentedJan. 29, 1924.v

UNITED STATES PATENT OFFICE.

CHESTER I. HALL, OF FORT WAYNE, INDIANA, ASSIGN OR TO GENERAL ELECTRICCOM- PANY, A CORPORATION OF NEW YORK.

BUZZER.

Application filed July 6,

T all whom it mdy concern:

Be it known that I, CHESTER I. HALL, a citizen of the United States,residin at Fort \Vayne, in the county of Allen,- tate of Indiana, haveinvented certain new and useful Improvements in Buzzers, of which thefollowing is a specification.

My invention relates to a buzzer and more particularly to one in whichno auxiliary contact devices are necessary.

In the past, b-uzzers whether adapted for operation with alternatingcurrent or direct current have been so arranged that contact makingarrangements were used, whereby the armature of the electromagnetincluded in the buzzer is rapidly vibrated in accordance with therapidity of the making and breaking of the electric circuit. iVith myinvention such auxilia contact devices are entirely obviated provi edthe buzzer is connected to an alternating current circuit- Furthermore,I arrange matters in such a.

way that the sound produced by the buzzer is primarly due to thestriking of the armature against the pole of theelectromagnet, and notto the vibration of the armature. This produces a distinct signal, andit is possible to operate the apparatus on commercial frequencies suchas or 60 cycles. It is thus the main object of my invention to providean electric signalling device extremely simple and inexpensive tomanufacture. Other objects making for simplicity and reliability willbecome apparent the description proceeds. For a better understanding ofmy invention reference is to be had to the accom anying drawing in whichFig. 1 is a lon itudinal sectional view of the buzzer;and ig. 2

is a top plan view of the same.

Referring now more in detail to the drawings, in which like referencecharacters refer to like parts throughout, a member 11 of magneticmaterial is provided, so de signed that it may conveniently be punchedfrom thin sheets. This member 11 serves both as a support for all of theparts of the buzzer and also as the core for the magnet. To form aU-shaped core the end 12 of the member 11 is bent up as shown to form 0one of the limbs of the U, and the central portion is struck up in theprocess of stamping to form the other limb 13. Upon this limb 13 islocated the energizing coil 14, the terminals of which are in electricalconnecof binding posts 15 and 16 1921. Serial No. 482,817.

supported on the member 11. One end 17 of the coil 14: is directlyconnected as by soldering to the post of shown in Fig. 2, while theother end 18 is grounded on the member or plate 11. The terminal 16 isinsulated from the member 11, while the terminal 15 is grounded on thismember. An aperture 19 is appropriately located for attaching the buzzerto any flat surface, such as a Wall. The mode of constructing member 11as herein described is extremely simple and inexpensive, and produces abuzzer having a minimum of parts.

The armature 20 of the electromagnet is made of a flat strip ofresilient material such as spring steel. It is attached at one of itsextremities 21 to the limb 12 of the U-shaped core by any appropriatemeans, such as the rivets 22. Its free extremity extends over the otherlimb 13 of the U-shaed core and is arranged so close to the pole t atupon energization of the magnet 14 this resilient armature periodicallystrikes this pole piece with a frequency equal to that of the source ofsupply. No auxiliary contacting devices are necessary for the operationof this buzzer.

The operation of the device is apparent from the foregoing description.All of the parts making up the buzzer are extremely simple and easilyassembled, and may be very inexpensively produced in large quantities.

While I have shown in the accompanying drawings but one embodiment of myinvention, I do not Wish to be limited thereto but aim to embrace in theappended claims all modifications falling fairly within the spirit andscope of my invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. An'electric signalling device of the alterna-ting current buzzer typecomprising a sheet metal stamping forming the base, terminal support andstationary magnetic circuit of the device, the stationary mag neticcircuit of said device being in the form of a U made by bending spacedpor- -ti0ns of said sheet metal stamping at right angles to the base, anenergizing coil wound on one limb of said U and connected to terminalson said base, and a member of resilient magnetic material secured at oneend to the upper end of one of said U limbs and extending adjacent theupper end of the the terminal 16 as other limb, thereby substantiallycompleting the magnetic circuit, whereby the free portionsv of saidresilient member is caused to vibrate against said other limb when thecoil is energized.

2. An electric signalling, device of the alternating enrrentbuzzer typecomprising an integral sheet metal stamping of magnetic material bent upat one end and struck up from the central portion to form a U-shapedcore and terminal support, terminals supported thereon, an energizingcoil on one of the limbs of the U-shaped core connected to saidterminals and a resilient armature of magnetic material supported on theother limb extending adjacent said first mentioned limb, thereby nearlycompleting the magnetic circuit of said core whereby the tree portion ofsaid arn'iature is adapted to vibrate against said first mentioned limbwhen said coil is energized by alternating current.

In witness whereof. l have hereunto set my hand this 1st dav o July.l92l.

CHEST ER I. HALL.

